1. Field of the Invention
The present invention relates to an exhaust device, and more particularly to an exhaust device capable of reciprocatively changing an outlet direction by using a temperature variation.
2. Description of Related Art
With the rapid progress of the electronic technique, various electronic products have developed towards the trend of being light, thin, short, and small. However, as the volume of the electronic product is greatly reduced, a problem of high heat exhaust occurs to various electronic devices. As for a computer, an electronic device, or a TV set, a heat sink fan is generally installed in the cases thereof, so as to solve the problem that heat sources are over-heated, for example, a chip, a central processing unit (CPU), an integrated circuit, and the like. Taking notebook computers for example, in most notebook computers, a heat sink fan is disposed within a host, an air inlet is disposed on a top surface or a bottom surface of the host, and an air outlet is disposed on a side edge of the host. Once the host begins to operate, the heat sink fan absorbs ambient cold air via the air inlet, and after the cold air performs heat exchange with a heat source (for example, CPU) of the notebook computer, the heat sink fan blows out the hot air via the air outlet.
In order to prevent foreign substances from entering the notebook computer from the air inlet or the air outlet, a plurality of fixed fins may be disposed at the air inlet or the air outlet, and most of the fins are vertical to the surface of the mainframe, such that the direction along which the air is blown out via the air outlet is vertical to the surface of the mainframe. For example, the air outlet of the notebook computer is disposed on the side edge of the host, and a user needs to place his/her hand on the side edge of the notebook computer where the air outlet is disposed (for example, when using a mouse), and thus, in this manner, the hot air blown out via the air outlet is directly blown to the user's hand, and as a result, a user may feel discomfortable.
Definitely, in order to solve the above problem, one of the feasible manners lies in that the air outlet of the notebook computer is designed as adjustable fins. For example, in the U.S. Pat. No. 6,229,701, a structure of heat dissipating slats at a ventilation hole of a notebook computer is disclosed, in which the heat dissipating slats are movably disposed at the ventilation hole, and the slats may overlap to close the ventilation hole or may form clearances at a certain angle under the control of a user. However, in the U.S. Pat. No. 6,229,701, the manner for adjusting the heat dissipating slats is quite complicated in terms of structure, and during operation, a user must control the angle of the heat dissipating slats so as to change the direction of the air blown out via the ventilation hole. If it intends to make the heat dissipating slats to swing back and forth at the ventilation hole, it may result in inconveniences in operation, or an electrical device (for example, a motor or a rotating shaft) is further required to be disposed on the heat dissipating slats, so as to enable the heat dissipating slats to swing back and forth, thereby resulting in an additional power consumption.